Mold-aligning means



April 24, 1928. r 1,667,129

T. MIDGLEY mow ALIGNING mans Filed March s, 1925 w #4 INVENTOR i QQQMWZM7 BY )3 2/ 2s 2 4- I4 33. 1 27 ATTORN Patented Apr. 24, 1928.

v UNITEDQSTA PATENT; OW

THOMAS MIDGLEY, OF HAMPDEN, MASSACHUSETTS, ASSTGNO CHIQOP EE FALLS,MASSACHUSETTS, A CORPORATION OF MASSA- COMPANY, or V cnusn'r'rs.

Application filed March 5,1925.

This invention relatesfto molds adapted for vulcamz ng articles such astire casings.

- In the manufactureof automobile tires the unvulcanized articles areenclosed within a metallic mold, usually of two part construction, andsubjectedto vulcanizing heat for the requisite period; Commonly theouter part ofthe molding cavity is formed with recesses in the reverseof the pattern desired upon the tread of the tire.

Untiltlie rubber has had a chance toflow into these recesses the moldhalves cannot come for the rubber is incompressible and the tirenecessarily is'made largeenough' so that it will. have sufficientmaterial to fill up these recesses. The usual aligning means forsecuring registry of the mold halves are defecfive in that they do notproperly align the mold until the halves have closely that they haveclosed upon the rubber, after which they cannot be shifted.

It is the object of my invention to provide mold aligning means by whichthe mold halves can be brought into registry before they have approachedclosely enough to grip the tire, and which will still have suflicientstrength to avoid breakageor bending. It is a further object to providemold aligning means which willhave no tendency to bind during closure ofthe mold, insuring a smooth and even action. Other objects will appearfrom the description and claims. Referring to the drawings, Fig. 1 is asection on line through two mold halves in closedposition, showing thealigning means fully engaged; Fig. 2 is a side'elevation of a' mold,par,- tially broken away to show vices Fig. 3 Is an enlarged detail online 3-3 of" Fig. 2; g r

Fig. 4 in a section on a reduced scale, 011 line 4-4 of Fig. 3;

Fig. 5 is a perspective view of a part of :he aligning device, invertedto show the construction of the bottom side as viewed in Figs. 1 and 3;and

Fig. 6 is a fragmentary view similar to Fig. 1 but showing the moldhalves in the process of closing.

The aligning device is shown in the present instance as applied to amold having mating halves or' side plates 10 and bead rings 11, but isapplicable to molds of other specific types. The molding recesses topro-' on the mold shown in Fig.

quite together,

YCIHGDt to describe one approached so 1-1 of Fig. 3,

the aligning delightness.

tral plane of the shouldered .at 26. and is provided with a a TO THEFISK RUBBER roLD-ALrGNINe. MEAivs.

s rial no. 13,100.

duce the tread pattern [on the tire'12 are shown at 13. Attached to themold, in the form shown, are rings 14 bent outwardly at 15 to formsupporting flanges upon which the mold may rest. when in stack formationin a heater. The aligning devices are shown as carried'by the rings 14but may be supported otherwise, as directly the side plates, whenapplied to molds of other types. Before speaking of the purpose of themanner of positioning the aligning devices 2, it will be conspecificform of device. Each device consists of two parts, a cam piece 16 and ablock 17. p In addition to these parts the mold itself performs onealigning function as will be described more fully below. The cam pieceis attached atone end to the ring 14 and flange 15 of one mold halfas bywelding indicated by 18. It has a cam surface 19, preferably rounded,for coaction with the block 17 and another cam surface 20, alsopreferably rounded, for coaction with the opposite mold half; Its bottomside is concaved at 21 to clear certain outwardly projecting parts ofthe mold. Po-

sitioning lugs 22 assist in locating "the cam piece during welding andin supporting it thereafter. Block 17 is secured, as y welding at 23, tothe opposite ring 14. In the drawings cam piece 16 is shown astriangular in form with a cam surface 19 on two corners. This is merelyfor convenience in being able to make the pieces in a single styleserving both for right and left hand. Only one surface i any function.piece 16 may be The upper surface of the hollowed The mold halveshave'surfaces 25 preferably coming together at or near the cenmold. Onering 14 is slanting portion 27 for coaction with the cam surface 20. Theother ring is suitably fitted to interlock with the first. a shoulder 28mating with shoulder 26 to insure complete, alignment when the moldhalves are assembled and pressed together.

Two sets'of aligning devices are used ina mold.both at one side of adiameter, as shown in Fig. 2, and preferably about 120 apart, instead ofbeing mounted diametrically opposite each other as mold dowels of theusual type are. This mounting permits 19 on asingle piece performs outas at 24: for

as f

the aligning devices to center the mold in two directions as it is beingclosed, due to the combined action of cam surfaces 19 and 20 of eachunit with the corresponding bearing surface.

In use, the two mold halves, with the uncured tire in one of them, arebrought to gether slowly, empty half onto the one containing the tire.Before the empty mold half contacts with the tire at all, it can readilybe steered so that the two cam pieces l6 contact with their respectiveblocks 17, and so that the cam surfaces 20 ride up on the slantingsurfaces 27 of the opposite mold half. This condition is illustrated inFig. 6, where the Wide separation of the mold halves is indicated by thespace between surfaces 25. The registration of the two parts of the moldproceeds smoothly and gradually, and yet positively, the ultimate resultbeing accurate alignment before the top mold half is pressed against therubber.

lVhile the preferred form of the device has been described necessarilyin some detail it will be apparent that changes in form may be made asrequired by the design of the preferably by lowering the to be fitted orasi limit circumferential movement in but one direction, said unitsbeing side of a diametral plane through the mold.

2. A tire mold separated into two sections upon a plane perpendicular tothe axis of the mold, one section having a; registering flangeprojecting towards the other mold half, a plurality of blocks both atone side of a diametral plane through the mold car ried by one moldsection, and a plurality of guiding pieces arranged similarly to theblocks but carried by the other mold section, each guiding piece havinga surface coacting with the projecting flange of the other mold sectionand surface coacting with one of the blocks, one block being 011 thereverse side of its guiding piece from another block.

THOMAS MIDGLE Y..

all located to one i

